This study aims to enlighten microfacies evolution and micropaleontological properties of the Tournaisian &amp / #8211 / Visean boundary in Aladag Unit (Central Taurides, Turkey). Two sections comprising dark shale and dark limestone alternations, including a fairly dolomitized part towards their top are measured. The microfacies analysis suggests a subtidal depositional environment. Foraminiferal assemblages were distinguished at Section AP and biozonation was documented. The biozonation separates the measured section into three zones, described as A, B and C. Zone A is scarce foraminifera fauna, and mainly contains Earlandia sp. Zone B is defined by appearance of a diversified foraminifera fauna and the first appearance of Lugtonia monilis (Malakhova, 1955) with Eoparastaffella sp. (morphotype 1). Zone C is defined according to the first appearance of Eoparastaffella simplex (Vdovenko, 1964) (morphotype 2) and foraminifers Laxaendothyra ex. gr. laxa. Tournaisian &amp / #8211 / Visean boundary is defined at the 60th sample, due to appearance of Eoparastaffella simplex (Vdovenko, 1964) (morphotype 2). Seven microfacies types in section AP, and six microfacies types in section PA are identified and, the intensely sampled part of the measured section AP is separated into 13 shallowing upward meter-scale cycles. These cycles, showing subtidal character are detected by both repetitions of microfacies and changes in abundance of foraminifers. A contrasting evaluation of the Tournaisian &amp / #8211 / Visean boundary of Taurides with Guangxi, South China and Dinant, Belgium is presented. The Chinese stratotype contains a diverse, more complete fauna of Tournaisian - Visean foraminifera, while the Belgium and Turkish sections are scarcer and most probably facies controlled.

Several hydrocarbon discoveries in the Marar Formation (Tournaisian and Viséan) were recently made in the Lower Carboniferous strata of the Ghadames and Murzuq Basins situated in SW Libya. Despite large exposures exhibiting thick sections, there is an absence of regional studies focusing on this stratigraphic interval and only rare case studies provide new sedimentary data. More generally, geological knowledge of Carboniferous in North Africa (Saharan Platform) is also understudied when compare to other regions of the world. Detail analyses of the sedimentary record on Saharan Platform may noticeably contribute to refine the current understanding of global geological episodes such as the Late Paleozoic Ice Age. The main aim of this study is to produce valuable field data for both industry and interpretations for assessing academic hypothesis. In order to develop accurate and detail correlations of sedimentary strata over long distances (over 350 km) a primary aims is to define a synchronous key marker horizon that is ideally detectable in both surface and subsurface datasets. A secondary aim is to characterise spatial variability and geometries of sedimentary bodies. Acquired during three fieldwork seasons in the area (along ca 385 km), over 4800 m of sedimentary logging, facies analyses and 800 outcrop gamma ray readings are compiled in this study. I therefore characterise the micro, meso, macro-scale geometries, regional distribution, gamma ray response and mineralogy of the Collenia stromatolites that mark the uppermost part of the Marar Formation. Mainly based on series of detailed sedimentary logging and photographic panoramas, two types of reservoirs facies are described: 1- several metres thick shorefaces sandstones that are continuous for several tens of kilometres; 2- several tens of metres thick incised valley in filled with fluvial sandstones of fewer lateral extend. A sea level curve, produced on basis of the detailed sequence stratigraphic framework of the area, reveals that eustasy almost solely explains relative changes of sea level during the Viséan. Considering the glacial record preserved on northern Gondwana during the same interval, we conclude that the onset of the Late Paleozoic Ice Age is older than uppermost Viséan and more gradual than previously thought.

The aim of this study is to investigate the Upper Visean substages, delineate the Visean - Serpukhovian boundary with calcareous foraminifera and interpret the foraminiferal evolution and sequence stratigraphical framework by using sedimentary cyclicity across the boundary section. For this purpose a 59,61 m thick stratigraphic section consisting of mainly limestone and partly sandstone and shale is measured in the Aziziye Gedigi and Oru&ccedil / oglu Formations in the Pinarbasi Region of Eastern Taurides. A detailed micropaleontological study has revealed presence of important foraminiferal groups namely, parathuramminids, earlandiids, endothyroids, archaediscids, biseriamminids, fusulinids, loeblichids, tournayellids and paleotextularids and 145 species and three biozones. The biozones are, in ascending order, Eostaffella ikensis &ndash / Vissarionovella tujmasensis Zone (Mikhailovsky / Late Visean), Endothyranopsis cf. sphaerica &ndash / Biseriella parva Zone (Venevsky / Late Visean) and Eostaffella pseudostruvei &ndash / Archaediscids @ tenuis stage Zone (Taurssk / Early Serpukhovian). A detailed microfacies analysis was carried out in order to understand the depositional history and sedimentary cyclicity and construct the sequence stratigraphic framework of the studied area. Three main depositional environments consisting of open marine, shoal or bank and tidal flat environments were interpreted based on the analysis of 12 major microfacies and 11 sub-microfacies types. Based on the vertical association of microfacies twenty-six cycles, two sequence boundaries and three sequences were recognized in the studied section and these two sequence boundaries, which correspond to the Mikhailovsky and Venevsky horizons, are the records of the global sea level changes during the Late Paleozoic Ice Age. Within this context Visean &ndash / Serpukhovian boundary falls in the transgressive system tract of the third sequence. The duration of cycles are calculated as 117 ky and interpreted as orbitally induced glacioeustatic cycles.

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